MSP430内部10位ADC的模数转化并通过串口发送

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MSP430内部10位ADC的模数转化并通过串口发送 [复制链接]

//******************************************************************************
// MSP-FET430P140 Demo - ADC12, Using the Internal Reference
// Description:

// MSP430F149
// ---------------
// | |
// Vin -->|P6.0/A0 |
// | |

//******************************************************************************

#include <msp430x14x.h>
#include"adc.h"
void DelayXms(unsigned int i); //delay about x ms
void uartInit(); //Init the usart0
void sendChar(char c); //send a char
void sendString(unsigned char *p); //send a string,input must be pointer
void int2charssend(int value); //convert the adc value to string and send it
void main(void)
{

int adcValue1,adcValue2;
WDTCTL = WDTPW+WDTHOLD; // Stop watchdog timer
uartInit(); //init the uart
while (1)
{

adcValue1 = GetAdcValue1();
// adcValue2 = GetAdcValue2();
int2charssend(adcValue1);
DelayXms(2000);

}
}
/****************************************************************************
*函数名: DelayXms() /
*作用：800KHz下大约1ms /
*返回值：无 /
*参数：一个字符 /

*****************************************************************************/
void DelayXms(unsigned int i){
unsigned int j;
for( ; i>0; i--){
for(j=0;j<200;j++);
}

}
/****************************************************************************
*函数名: int2charssend() /
*作用：启动ADC转化之后，将P6.0口的模拟信号转化为数字量（0-4096）并通过串口发送 /
*返回值：无 /
*参数：整数 /

*****************************************************************************/
void int2charssend(int value){
unsigned char s[] = "0000";
unsigned char *p;
int bits=0,ten = 0,hundred = 0,thousand = 0;
thousand = value/1000;
hundred = value%1000/100;
ten = value%100/10;
bits = value%10;
s[0]=thousand+'0';
s[1]=hundred+'0';
s[2]=ten+'0';
s[3]=bits+'0';
p = s;
sendString(p);
}

/****************************************************************************
*函数名: sendChar() /
*作用：USART0发送一个字符 /
*返回值：无 /
*参数：一个字符 /

*****************************************************************************/
void sendChar(char c){
TXBUF0=c;
while((UTCTL0&0X01)==0);//等待数据发送完毕
}
/****************************************************************************
*函数名: sendString() /
*作用：USART0发送字符串 /
*返回值：无 /
*参数：char型指针 /

*****************************************************************************/
void sendString(unsigned char *p){

while(*p!='\0'){
TXBUF0=*p++;
while((UTCTL0&0X01)==0);//等待数据发送完毕
}
}
/****************************************************************************
*函数名: uartInit() /
*作用：USART0的初始化配置，使用P3.4和P3.5，不使用中断 /
*返回值：无 /
*参数：无 / /
*****************************************************************************/
void uartInit(){
P3DIR|=BIT4+BIT5;
P3SEL|=BIT4+BIT5;

ME1 |= UTXE0 + URXE0; // 使能USART0收发
UCTL0 |= CHAR; // 8-bit 数据，一位停止位
UTCTL0 |= SSEL0; // 选择时钟，UCLK = ACLK，32768
UBR00 = 0x03; // 32k/9600
UBR10 = 0x00; //
UMCTL0 = 0x4a; // Modulation
UCTL0 &= ~SWRST; // 初始化UART0状态机，一般要设置好串口之后才复位
}
其中需要添加ADC的头文件和源文件，并且要把adc.c包含到工程中去

adc.c如下：

#include<msp430x14x.h>

unsigned int GetAdcValue1(void){
unsigned int value; //digital value
P6SEL |= BIT0+BIT1; // Enable A/D channel A0
ADC12CTL0 = ADC12ON+SHT0_6; // Turn on and set up ADC12
ADC12CTL1 = SHP; // Use sampling timer
ADC12MCTL0 =INCH_0+ SREF_0; // Vr+=VCC,Vr+=VSS,switch the inch1
ADC12CTL0 |= ENC; // Enable conversions
ADC12MEM0 = 0; //首先对转化结果的寄存器清零
ADC12CTL0 |= ADC12SC; // Start conversion
while ((ADC12IFG & BIT0)==0);
_NOP(); // SET BREAKPOINT HERE
value = ADC12MEM0;
return value;
}
unsigned int GetAdcValue2(void){
unsigned int value; //digital value
P6SEL |= BIT0+BIT1; // Enable A/D channel A0
ADC12CTL0 = ADC12ON+SHT0_6; // Turn on and set up ADC12
ADC12CTL1 = SHP; // Use sampling timer
ADC12MCTL0 =INCH_1+ SREF_0; // Vr+=VCC,Vr+=VSS,switch the inch1
ADC12CTL0 |= ENC; // Enable conversions
ADC12MEM0 = 0; //首先对转化结果的寄存器清零
ADC12CTL0 |= ADC12SC; // Start conversion
while ((ADC12IFG & BIT0)==0);
_NOP(); // SET BREAKPOINT HERE
value = ADC12MEM0;
return value;
}
adc.h如下：

#ifndef _ADC_H_
#define _ADC_H_
unsigned int GetAdcValue1(void); //start adc and return a digital value (0-4096)
unsigned int GetAdcValue2(void); //start adc and return a digital value (0-4096)
#endif

下面给出TI官方的例程供参考：

//******************************************************************************
// MSP-FET430P140 Demo - ADC12, Sample A0, Set P1.0 if A0 > 0.5*AVcc
//
// Description: A single sample is made on A0 with reference to AVcc.
// Software sets ADC10SC to start sample and conversion - ADC12SC
// automatically cleared at EOC. ADC12 internal oscillator times sample (16x)
// and conversion. In Mainloop MSP430 waits in LPM0 to save power until ADC12
// conversion complete, ADC12_ISR will force exit from LPM0 in Mainloop on
// reti. If A0 > 0.5*AVcc, P1.0 set, else reset.
//
//                MSP430F149
//             -----------------
//         /|\|              XIN|-
//          | |                 |
//          --|RST          XOUT|-
//            |                 |
//      Vin-->|P6.0/A0      P1.0|--> LED
//
// M. Buccini
// Texas Instruments Inc.
// Feb 2005
// Built with IAR Embedded Workbench Version: 3.21A
//******************************************************************************

#include <msp430x14x.h>

void main(void)
{
  WDTCTL = WDTPW + WDTHOLD;                 // Stop WDT
  ADC12CTL0 = SHT0_2 + ADC12ON;             // Set sampling time, turn on ADC12
  ADC12CTL1 = SHP;                          // Use sampling timer
  ADC12IE = 0x01;                           // Enable interrupt
  ADC12CTL0 |= ENC;                         // Conversion enabled
  P6SEL |= 0x01;                            // P6.0 ADC option select
  P1DIR |= 0x01;                            // P1.0 output

  for (;;)
  {
    ADC12CTL0 |= ADC12SC;                   // Sampling open
    _BIS_SR(CPUOFF + GIE);                  // LPM0, ADC12_ISR will force exit
  }
}

// ADC12 interrupt service routine
#pragma vector=ADC_VECTOR
__interrupt void ADC12_ISR (void)
{
    if (ADC12MEM0 < 0x7FF)
      P1OUT &= ~0x01;                       // Clear P1.0 LED off
    else
      P1OUT |= 0x01;                        // Set P1.0 LED on
    _BIC_SR_IRQ(CPUOFF);                    // Clear CPUOFF bit from 0(SR)
}